There has been an increasing social concern of energy saving due to global warming for controlling environmental apparatus, for example, air conditioning apparatus installed in buildings. BEMS (Building and Energy Management System) is now proposed to optimize energy management in the building. Actually, most of building administrators do not always operate and manage the environmental apparatus properly in view of energy-saving and comfortableness. Especially for temperature control of an enclosed residential space in the building where the comfortableness may conflict with the energy-saving, it has been a common practice to rely solely upon a customary temperature setting and adjust the temperature setting upon request by residents.
Since the temperature control has been made without sufficient consideration of the building characteristics and the resident's preference, the residential space is not always kept at an optimum condition that the residents feel comfort, and even the energy for the air conditioning apparatus may be wasted. Further, the residents may have complaints about that he or she is under the temperature control by the building administrator and is not able to control the environment on his or her own initiative.
In order to cope with the above problem, Japanese Patent Publication No. 2004-205202 proposes a system for controlling the temperature environment in consideration of time-varying resident's preference in combination with the building characteristics. The system is configured to collect residents' demands for the temperature environment on a real-time basis from a communication device, for example, a personal computer belonging to the individual residents, to determine the temperature setting based upon the collected demands, and to control the temperature environment in accordance with the resident's preference as well as the building characteristics representing the temperature difference between the general temperature being monitored at a limited point in the building and the actual temperature at the residential space.
The system is configured to request the residents to submit the environmental demands and to compare the counts of two opposed demands, i.e., “raise temperature” and “lower temperature” in order to obtain a predominant one of the demands by use of a specific algorithm. Then, the system determines a control project of controlling the air-conditioning apparatus in a direction of satisfying the predominant demand. The algorithm in the above system utilizes a first proportion (P1) of the count of the first demand, i.e., temperature lowering demand in the total number of the residents, and a second proportion (P2) of the count of the second demand, i.e., temperature raising demand in the total number of the residents. Then, the algorithm relies upon a 25% rule, as shown in FIG. 11, and returns a result of lowering the temperature when the first proportion (P1) is higher than 25% and at the same time the second proportion (P2) is lower than 25%, i.e., when the first proportion and the second proportion are within a temperature lowering zone as indicated in FIG. 11 by “▾”. When, on the other hand, the second proportion (P2) exceeds 25% and the first proportion (P1) is lower than 25%, i.e., the first and second proportions are within a temperature raising zone as indicated by “▴”, the algorithm returns the result of raising the temperature. When the first and second proportions (P1, P2) are both lower than 25% or both higher than 25%, i.e., the first and second proportions are within a neutral zone as indicated by “▪”, the algorithm returns the result of keeping the temperature.
The use of the above algorithm is found satisfactory so long as the neutral zone “▪” can be selected. That is, when a response ratio of the added counts of the first and second demands to the total number of the response is higher or lower than 50%, the algorithm can well acknowledge that majority of the residents do not want to raise or lower the temperature. However, for example, when the response ratio is 50%, and both of the first and second proportions are 25%, the algorithm cannot return the result of keeping the temperature. In the situation where the response ratio is around 50%, a slight variation in the first and second proportions results in either of raising and lowering the temperature, while affording no choice of keeping the temperature in consideration of the presence of the residents giving no particular demands or implying to keeping the temperature. Consequently, the system cannot decide to keep the temperature, failing to control the air-conditioning apparatus in consistent with the demands by the residents